The development of embryos and the spread of cancer are dependent upon adhesive interactions of cells. This laboratory has been engaged in cell adhesion studies for two decades. Thirty of our publications in refereed journals have been co-authored by our undergraduate and pre-masters students (81 student co-author citations). The lab has been continuously funded from a variety of research and science education sources (totaling about $2 million) and therefore this request is for Associate status. Presently 25 students are engaged in research in this laboratory, many of whom are underrepresented, including 2 MARC and 4 MAERC Fellows, who already have made 9 presentations at professional meetings in the past year. 36 students from this lab are now Ph.D's, in Ph.D. programs and/or are involved in biomedical science. Our ongoing projects investigate the mechanisms of cell-cell adhesion in the sea urchin embryo, a model for such studies because of material availability, complete transparency of the embryos and simplicity of the medium (sea water). The MBRS students, just like our MARC and MAERC students, will be fully involved in experimental design, execution, preparation for publication and presentation of the research. Using western cell adhesion and polyacrylamide gel electrophoresis, the students will characterize cell adhesion molecules isolated from living sea urchin blastula cells that promote cell adhesion in a species-specific and developmental stage specific manner. Using beads derivatized with specific sugars and lectins, reduced (non-agglutinating) lectins and hapten sugars, they will study the role of specific sugars and sugar receptors in the adhesion mechanism. They will also become engaged in exciting new experiments, that involve entering the intact, living embryo with sugar, enzyme and reduced lectin reagents that will help us determine if specific sugars are involved in adhesive interactions that are pivotal in morphogenesis. These will be among the first experiments anywhere that probe physiologically important in vivo adhesion mechanisms in this model system.